1991 ACURA NSX torque

28. Tighten bolts and nuts finger tight at six points as

shown below.

29. Starting with nut torque all bolts and nuts, in a

clockwise pattern in three steps.

NOTE: Excessive tightening can cause distortion of

oil pan gasket and oil leakage.

Torque: 14 N-m (1.4 kg-m, 10 lb-ft)ProCarManuals.com

Intake Air System

Intake Air Bypass (IAB) Control System

Description

Satisfactory power performance is achieved by closing and opening the intake air bypass (IAB) control valves. High torque

at low engine speed is achieved when the valves are closed, whereas high power at high engine speed is achieved when

the valves are opened.

INTAKE AIR BYPASS (IAB) CONTROL

SOLENOID VALVE ON

ENGINE SPEED IS ABOVE 4,800 rpm

OPEN: HIGH ENGINE SPEED

IAB CONTROL

SOLENOID

VALVE

To No. 5 BACK-UP LIGHTS

ALTERNATOR TURN SIGNALS

(15 A) FUSE

IAB

CONTROL

DIAPHRAGM

IAB

CONTROL

VALVE
CLOSED: LOW ENGINE SPEEDProCarManuals.com

6. Install the release bearing on the pressure plate.

7. Install the pressure plate.
NOTE:
Align the mark on the mid plate with the mark onthe pressure plate.
After installing, make sure the release bearing is
secure.

Align the marks.

PRESSURE PLATE

RELEASE BEARING

PRESSURE PLATE

(P/N 08798-9002)
RELEASE

BEARING
Place the diaphragm spring fingers

in the groove of the release bearing.
9. Remove the special tools.

10. Initialize the mid plate guides (see page 12-14

('93-'96), 12-16 ('91-'92 Models).
MOUNTING BOLT

8 x
1.25
mm
22 N·m (2.2 kg-m, 16 Ib-ft)

8. Torque the mounting bolts in a crisscross pattern
as shown. Tighten them several steps to prevent

warping the diaphragm spring.

NOTE: Place the diaphragm spring fingers in the
groove of the release bearing.ProCarManuals.com

Mainshaft Thrus t Shi m
Adjustmen t
7. Instal l th e bal l bearin g ont o th e mainshaf t usin g th e
specia l tools , the n instal l th e 7 5 m m sprin g washe r
an d mainshaf t assembl y int o th e clutc h housing .
DRIVER, 4 0 m m I.D .07746 - 0030100
ATTACHMENT , 3 5 m m I.D .07746 - 0030400
BAL L BEARIN G
8. Instal l th e transmissio n housing .
Torque : 4 5 N- m (4. 5 kg-m , 3 3 Ib-ft )
9. Chec k th e thrus t clearanc e in th e manne r describe d
below.
NOTE : Carr y ou t th e measuremen t a t norma l roo m
temperature .
a . Slid e th e mainshaf t bas e ove r th e mainshaft ,
b . Attac h th e mainshaf t holde r t o th e mainshaf t a s
follows :
• Back-ou t th e mainshaf t holde r bol t an d
loose n th e tw o he x bolts .
• Fi t th e holde r ove r th e mainshaf t s o it s li p i s
toward s th e transmission .
• Alig n th e mainshaf t holder' s li p aroun d th e
groov e a t th e insid e of the mainshaf t splines ,
then tighte n th e he x bolts .
HEX BOL T
MAINSHAFT
HOLDER BOL T
MAINSHAF THOLDER07GAJ - PG20110
MAINSHAF T BAS E07GAJ - PG20130
c. Sea t th e mainshaf t full y b y tappin g it s en d
wit h a plasti c hammer .
d . Threa d th e mainshaf t holde r bol t i n unti l i t
jus t contact s th e wid e surfac e o f th e main -
shaf t base .
e . Zer o a dia l gaug e o n th e en d o f th e mainshaft .
DIAL GAUG E
f. Tur n th e mainshaf t holde r bol t clockwise ; sto p
turnin g whe n th e dia l gaug e ha s reache d it s
maximu m movement . Th e readin g o n dia l
gauge i s th e amoun t o f mainshaf t en d play .
CAUTION : Turnin g th e shaf t holde r bol t mor e
tha n 6 0 degree s afte r th e needl e o f th e dia l
gaug e stop s movin g ma y damag e th e
transmission .
g. I f th e readin g i s withi n th e standard , th e
clearanc e is correct .
I f th e readin g i s no t withi n th e standard , rechec k
th e shi m thickness .
Standard :
0.14-0.21 mm (0.006-0.00 8 in)
ProCarManuals.com

1 5 . Tighte n th e transmissio n housin g attachin g bolt s i n
a crisscros s patter n in severa l step s a s show n below .
Torque : 4 5 N- m (4. 5 kg-m , 3 3 Ib-ft )
16 . Instal l th e 3 6 m m sealin g bolt .
NOTE :
Apply liquid gaske t (P/ N 08718-0001 ) to
th e threads .
17 . Instal l th e stee l balls , springs , an d sealin g bolts .
NOTE : Appl y liqui d gaske t (P/ N 08718-0001 ) t o
th e threads , bu t don' t plu g th e hol e with liquid
gasket .
STEEL BAL L(3/8 in)
14 x 1. 0 m m SEALIN G BOL T33 N- m (3. 3 kg-m , 2 4 Ib-ft )
SPRIN G (L . 2 5 mm )
3 6 m m SEALIN G BOL T
3 5 N- m (3. 5 kg-m , 2 5 Ib-ft )
SPRIN G
(L. 24. 2 mm ) 12 x 1. 0 m m
SEALIN G BOL T22 N- m (2. 2 kg-m ,16 Ib-ft )
STEE L BAL L(5/16 in)
16 x 1. 0 m mSEALIN G
BOL T COM P
42 N- m(4.2 kg-m , 3 0 Ib-ft )
18. Instal l th e back-u p ligh t switc h an d neutra l positio n
switch.
NOTE: Appl y liqui d gaske t (P/ N 08718-0001 ) t o
the threads .
19. Instal l th e differentia l spee d senso r an d vehicl e spee d
senso r (VSS) .
VSS(O-RIN G Replace. ) NEUTRA
L POSITIO N
SWITCH25 N- m (2. 5 kg-m ,18 Ib-ft )
DIFFERENTIA L
SPEE D SENSO R
BACK-UP LIGH T SWITC H
2 5 N- m (2. 5 kg-m , 1 8 Ib-ft )
A: 8 x 1.2 5 mm24 N- m (2. 4 kg-m , 1 7 Ib-ft )B: 8 x 1.2 5 mm26 N- m (2. 6 kg-m , 1 9 Ib-ft )C: 6 x 1. 0 m m12 N- m (1. 2 kg-m , 9 Ib-ft )
ProCarManuals.com

16. Tighte n th e mountin g bolt s i n a crisscros s patter n
i n severa l steps .
8 x 1. 0 m m SPECIA L BOLT S
4 0 N- m (4. 0 kg-m , 2 9 Ib-ft )
BENC H
VIS E
DIFFERENTIA LINSPECTION TOOL S07MAJ-PR9010 0
• 11 2 m m shi m adjustmen t
17 . Measur e th e prese t torqu e (se e pag e 15-4 ).
Standard :
60-140 N-m (6-1 4 kg-m ,
43-10 1 Ib-ft)
11 2 m m SHI M
Standar d shi m
If th e prese t torqu e i s mor e tha n th e standard ,
selec t a thinne r 11 2 m m shim , an d rechec k th e
prese t torque .
I f th e prese t torqu e i s les s tha n th e standard ,
selec t a thicke r 11 2 m m shim , an d rechec k th e
prese t torque .
ProCarManuals.com

I
Oil Seal

Removal

16. Tighten the mounting bolts in a crisscross pattern
in several steps.

8 x 1.0 mm SPECIAL BOLTS

40 N·m
(4.0 kg-m,
29 Ib ft)
1. Remove the differential assembly.
2. Remove the oil seat from the transmission housing.

OIL SEAL

Replace.

DIFFERENTIAL

INSPECTION TOOLS

07MAJ–PR90100

BENCH

VISE

TRANSMISSION HOUSING

112 mm shim adjustment
17. Measure the preset torque (see page 15-4),
Standard:
60-140
N·m
(6-14
kg-m.
43-101
Ib-ft)

112 mm SHIM Standard shim3. Remove the oil seal from the clutch housing.

A
B

C

D
E

F
H

J
Part Number

41261
—PR8—000

41262—PR8—000

41263—PR8—000

41264—PR8—-000

41265—PR8—000

41266— PR8—000

41267—PR8—000
41268—PR8—000

41269—-PR8—000

41270—PR8—000
Thickness

1.2 mm (0.0472 in)

1.4 mm (0.0551 in)

1.6 mm (0.0630 in)

1.8 mm (0.0709 in)

2.0 mm (0.0787 in)

2.2 mm (0.0866 in)

2.4 mm (0.0945 in)

2.6 mm (0.1024 in)

2.8 mm (0.1102 in)

3.0 mm (0,1181 in)
If the preset torque is more than the standard,
select a thinner 112 mm shim, and recheck the
preset torque.
If the preset torque is less than the standard,
select a thicker 112 mm shim, and recheck the
preset torque.

CLUTCH HOUSING

OIL SEAL
Replace.
ProCarManuals.com

2. Instal l th e standar d shi m an d bearin g oute r rac e in -
t o th e transmissio n housin g usin g th e specia l tool s
a s shown .
CAUTION : D o no t us e mor e tha n on e shi m to ad -
jus t th e bearin g preload .
NOTE:
• Instal l th e bearin g oute r rac e squarely .
• Chec k tha t ther e i s n o clearanc e betwee n th e
bearin g oute r race , shi m an d transmissio n
housing .
7 5 m m THRUS T SHIM :
Standard shi m 3
. Lubricat e th e tapere d rolle r bearin g wit h transmis -
sio n oil , the n instal l th e differential .
4 . Instal l th e transmissio n housing .
NOTE : D o no t instal l th e mainshaft , countershaft ,
an d revers e idl e gea r shaft .
Torque : 4 5 N- m (4. 5 kg-m , 3 3 Ib-ft )
5 . Rotat e th e differentia l assembl y i n bot h direction s
t o sea t th e bearings .
6. Measur e th e startin g torqu e o f th e differentia l
assembly wit h a specia l too l an d a torqu e wrenc h
a s shown .
NOTE : Measur e th e bearin g preloa d a t norma l
roo m temperatur e i n bot h directions .
Standard : 2.0-3. 0 N- m (20-3 0 kg-cm ,
17-26 lb-in )
TORQUE WRENC H
DIFFERENTIA LINSPECTION TOOL S07MAJ-PR90100
7. I f th e bearin g preloa d i s no t withi n th e standard ,
selec t th e shi m tha t wil l giv e yo u th e correc t
preload , an d recheck .
NOTE : Changin g on e o f th e shim s t o th e nex t siz e
wil l increas e o r decreas e preloa d abou t 0. 3- 0. 4
N- m (3- 4 kg-cm , 2.60-3.4 7 Ib-in) .
DRIVE R07749-0010000
ATTACHMENT ,72 x 75 m m07746-0010600
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